CD agrees cultivated plants may begin to vary after some time and then may vary suddenly, but cautions JDH on lack of evidence. His explanation is that small variations are ignored until they accumulate.

Transcription

Down Bromley Kent

12th

My dear Hooker

I have the old M.S, otherwise the loss would have killed me! The worst is now that it will cause delay in getting to press, &
far worst of all I lose all advantage of you having looked over my chapter,
except the third part returned.— I am very sorry Mrs Hooker
took the trouble of copying the two pages.—

Do not, pray, think of giving up coming here; I
shd extremely regret it. With you I can go
away the moment my stomach feels bad, & that is the important point for
me. I am rather sorry for my private pleasure, though glad for guests' sakes,
that our House will be so full.—

I much fear after all we shall not be able to send for you: but let me know train by
which you will come to Bromley (Mason Hill) & then I will send if I
can, if not you must take fly, & always plenty there.

I would advise you to be cautious about stating so broadly (I thought that you perhaps
knew of distinct cases unknown to me) about species not varying for many
generations & then suddenly varying. To a certain extent I quite
believe it; ie that a plant will not vary until after some few generations (perhaps
dozen or so) & then will begin to vary possibly suddenly, more likely
gradually. But even my belief in this is grounded on very few facts.— I
believe another & very distinct explanation may be given of a sort of current
belief in the doctrine, viz that variations are often not attended to, & till
they are attended to & accumulated, they make no show.—

Ever yours | C. Darwin

I have worked this notion up in (as it seems to me) an important manner in my Ch. on
Domestication of Animals & Plants.

Hooker had accidently put the fair copy of CD's chapters on geographical
distribution in the drawer in which Frances Harriet Hooker kept paper for the children
to draw on. In a letter to Thomas Henry Huxley, Hooker related how the children
‘of course had a drawing fit ever since’ so that nearly a quarter of
the manuscript had vanished before Hooker came to read it (L. Huxley ed. 1918,
1: 495–6). Hooker continued: I feel brutified, if not brutalised,
for poor D. is so bad that he could hardly get steam up to finish what he
did. How I wish he could stamp and fume at me—instead of taking it so
good-humouredly as he will.

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f2 2453.f2

The Darwins were expecting Emma's brother Francis Wedgwood and his family
from Barleston, Staffordshire. In addition to Hooker, the two Thorley sisters came,
presumably to help with the children.

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f3 2453.f3

See Origin, pp. 41–2, where CD cited the example of the
strawberry: I have seen it gravely remarked, that it was most fortunate that
the strawberry began to vary just when gardeners began to attend closely to this
plant. No doubt the strawberry had always varied since it was cultivated, but the
slight varieties had been neglected. As soon, however, as gardeners picked out
individual plants with slightly larger, earlier, or better fruit, and raised seedlings
from them, and again picked out the best seedlings and bred from them, then, there
appeared (aided by some crossing with distinct species) those many admirable varieties
of the strawberry which have been raised during the last thirty or forty
years. Hooker discussed the point in Hooker 1859, p. viii.